The technology disclosed here relates to a closure system for a pressurized container system of a motor vehicle.
Motor vehicles with pressurized container systems are known as such. They comprise a refueling connection, also called a tank nozzle or tank receptacle, which lies behind a fuel filler flap. In order to protect the tank nozzle from dirt and/or condensation or formation of ice, the tank nozzle is protected by a protective cap. For refueling, a fueling nozzle is plugged onto the refueling connection, the fueling nozzle taking up a comparatively large amount of construction space. The fuel filler flap can therefore be closed even if the protective cap is not located on the refueling connection at all or is not correctly positioned. The refueling connection and the following hydrogen conducting components may become untight due to dust and other dirt or their function may be interfered with in some other way. Complete destruction of components is also possible.
It is a preferred object of the technology disclosed here to reduce or to eliminate the disadvantages of the previously known solutions. Further preferred objects emerge from the advantageous effects of the technology disclosed here.
The technology disclosed here relates to a closure system for a pressurized container system for storing fuel in a motor vehicle which is operated, for example, with compressed natural gas (CNG) or liquefied natural gas (LNG) or with hydrogen. The pressurized container can be, for example, a cryogenic pressurized container or a high pressure gas container. High pressure gas containers are designed so as, substantially at ambient temperatures, to store fuel (e.g., hydrogen) permanently at a maximum operating pressure (MOP) of above approx. 350 barg (=positive pressure in relation to the atmospheric pressure), furthermore preferably of above approx. 500 barg and particularly preferably of over approx. 700 barg. A cryogenic pressurized container is suitable in particular for storing the fuel at temperatures which lie significantly below the operating temperature (what is meant is the temperature range of the vehicle surroundings in which the vehicle is intended to be operated) of the motor vehicle, for example at least 50 kelvin, preferably at least 100 kelvin or at least 150 kelvin below the operating temperature of the motor vehicle (as a rule approx. 40° C. to approx. +85° C.).
The closure system comprises at least one fuel filler flap and at least one refueling connection or tank nozzle or tank receptacle (the term “refueling connection” is used for simplification below). The refueling connection has a non-return valve closing the refueling system, and a protective cap. The non-return valve is designed to avoid fuel from flowing back into the refueling system or fuel flowing out of the pressurized container system through the refueling connection. In particular, a refueling connection as indicated in the standard SAE J2600:2002 (where it is called a “receptacle”) is involved. As a rule, one end of the refueling connection is designed to be connected to a fueling nozzle, whereas the other end is fluidically connected via a fuel conducting line system to the at least one pressurized container. That end of the refueling connection which is connectable to the fueling nozzle and the non-return valve can be accommodated in a constructional unit. Furthermore, the two elements can also be arranged adjacent to each other in different housings. The non-return valve therefore takes on the function of the fuel filler cover, which closes a filling opening, of a conventional fuel tank for diesel or petrol.
The protective cap is designed to be pluggable onto the refueling connection. The protective cap protects the refueling connection against possible impurities or other environmental influences. The protective cap is expediently designed to radially seal the refueling connection. For this purpose, the protective cap can have a base from which at least one side wall extends. This side wall can lie in a sealing manner against a circumferential wall of the refueling connection. By means of such a radial seal, large tolerances can be compensated for without substantial closing forces being necessary. In particular, the plugging on can be configured such that the protective cap can be slid on and cannot be screwed on at the same time.
The fuel filler flap is arranged as in the case of conventional motor vehicles. As a rule, it ends flush with the directly surrounding regions of the outer contour of the motor vehicle body, or contour thereof which is visible from the outside (also outer skin of the motor vehicle body below). In particular, the fuel filler flap covers the refueling connection and possible further interfaces, such as, for example, communication interfaces, which are used during the refueling.
The refueling connection and the other interfaces are arranged in a refueling compartment B which is set back from the outer skin of the vehicle body and is covered by the fuel filler flap.
The fuel filler flap, on the side facing the refueling compartment B, has such a contour that the fuel filler flap can be closed only if the protective cap is fitted on the refueling connection. That is, in the closed state of the fuel filler flap, the contour projects into the refueling compartment B to an extent such that, in the closed state of the fuel filler flap, no free space for the protective cap and/or for a loss-preventing means of the protective cap is available in the refueling compartment B, into which free space the protective cap and/or the loss-preventing means is/are disposable in a destruction-free manner, unless the protective cap is mounted onto the refueling connection. It can thereby be ensured in a simple, robust, cost effective and/or error proof manner that the protective cap is plugged on before the fuel filler flap is closed.
As an alternative to the aforementioned contour, the protective cap can also be mounted on that side of the fuel filler flap which faces the refueling compartment, wherein the protective cap is plugged onto the refueling connection by closing of the fuel filler flap. For this purpose, the protective cap can be adhesively bonded or injection molded onto the fuel filler flap. The protective cap is preferably of elastic design such that possible manufacturing tolerances can be compensated for and also a pivoting closing movement of the fuel filler flap is made possible. For this purpose, use can preferably be made of a rubber material.
The loss-preventing means can be designed and arranged in such a manner that the protective cap is not disposable in a destruction-free manner outside the refueling compartment B in such a manner that the fuel filler flap would be or is also closable without the protective cap being located in the refueling compartment B. The loss-preventing means can restrict the spatial positioning of the protective cap in such a manner that, in the closed state of the fuel filler flap, the protective cap is not disposable outside the refueling compartment B laterally next to the fuel filler flap, wherein laterally here comprises at the top, bottom, on the left and/or right next to the fuel filler flap. The loss-preventing means can have a thickness which is greater than a gap S between the fuel filler flap and those regions of the outer skin of the vehicle body that are directly adjacent to the fuel filler flap, and therefore the fuel filler flap cannot close if the loss-preventing means runs through the gap S.
In other words, for the present application, the inner side of the fuel filler cover is shaped in particular in such a manner that closing of the fuel filler cover is possible only upon correct positioning of the protective cap.
This is possible by means of a “key lock arrangement” of protective cap and inner side of the fuel filler cover.
According to the teaching disclosed here, the loss-preventing means is intended to be dimensioned in such a manner that closing of the fuel filler flap is not possible unless the protective cap is located on the tank nozzle. For this purpose, the thickness of the loss-preventing means can be greater than a gap on the fuel filler flap. Alternatively or in addition, the loss-preventing means can be configured by dimensioning and connection point in such a manner that the protective cap cannot be brought in a destruction-free manner outside the refueling compartment. In other words, the action radius of the protective cap is therefore restricted to the compartment which is closable by the fuel filler flap.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.